As experience has increased, surgeons have come to view mitral valve repair as the treatment of choice in patients with mitral regurgitation (MR) due to myxomatous leaflet degeneration and ischemic mitral regurgitation (IMR). However, recent long-term studies have indicated that the recurrence of significant MR after repair is much higher than previously believed, particularly in patients with IMR. The majority of repair failures are stress related. Leaflet curvature is an important determinant of valve stress. Therefore, repair devices and techniques which maximize leaflet curvature should reduce valvular stress and increase repair durability. During the previous funding cycle we proved the hypothesis that saddle shaped annuloplasty accentuates leaflet curvature when compared to flat annuloplasty in an ovine repair model. We have developed software algorithms that allow the use of real- time three dimensional echocardiography (rt-3DE) to non-invasively assess annular and leaflet geometry. This work has been very productive and has stimulated great interest in both the field of annuloplasty ring design and the field of quantitative rt-3DE imaging. Our specific aim is to evaluate the growing number of complex repair techniques being proposed to improve the currently poor results of IMR repair. We will study these techniques in an ovine model of IMR using our newly developed rt-3DE imaging algorithms. Each repair will be evaluated regarding its effect on leaflet curvature, leaflet tethering, ventricular function and durability. Such an assessment will allow only the most promising techniques to be performed in humans. PUBLIC HEALTH RELEVANCE: The specific aim of the current proposal is to evaluate the growing number of annular, leaflet and subannular repair techniques being proposed (without any true evidence of efficacy) to improve the currently poor clinical results of ischemic mitral regurgitation (IMR) repair. We will evaluate the efficacy of these techniques in an ovine model of IMR repair using our previously develop 3D echo imaging algorithms. Such an assessment will allow only the most promising techniques to be performed in humans.